From the people that have been joining Avion via these, they are now cadet programs. You pay, but you get a salary equal to every other FO in the company with all the benefits. Your contract is exactly the same as everyone else's.
Eaglejet gets you to join as TR Cadet, BAA gets you to join as NTR. I've heard some horror stories about BAA cadets, but eaglejet ones are mostly satisfied.
Just informing on how it's working. I'll be honest, if I didn't manage to join without paying, I'd definitely go through one of these. I can make money back, but not time. Everyone saying all the companies are hiring, but the reality is, from the 100% of pilots I know that finished since 2021, only 5% managed to join the big boys... And 4.5% out of those 5% joined via Ryanair (which has the same thing. You pay for type rating and 500h and you get a salary).